1. Field of the Invention
The present invention relates to the use of polymers as detergent additives for inhibiting dye transfer during the wash, to polymers that contain aminal, hemiaminal and/or aminal-acetal structures, and to detergents containing these polymers.
2. Discussion of the Background
DE-B-22 32 353 discloses detergent and cleaner mixtures which consist essentially of 95 to 60% by weight of nonionic detergents and 5 to 40% by weight of a partially or completely water-soluble polyvinylpyrrolidone and are essentially free of anionic surfactants. Polymers of vinylpyrrolidone prevent the transfer of dye from colored to white textiles during the wash. Polymers of vinylpyrrolidone have molecular weights within the range from about 10 000 to about 1 000 000. Both homopolymers and copolymers of vinylpyrrolidone are suitable. Acrylonitrile and maleic anhydride are mentioned as suitable comonomers. However, the effectiveness of vinylpyrrolidone polymer dye transfer inhibitors is strongly impaired by anionic surfactants.
DE-A-28 14 287 discloses detergent and cleaner compositions containing anionic and/or nonionic surfactants, builders and other customary detergent additives and also--as discoloration-inhibiting additives--from 0.1 to 10% by weight of water-soluble or water-dispersible homo- or copolymers of N-vinylimidazole. These polymers, however, are insufficiently active against a number of color stains.
EP-A-0 461 399 and EP-A-0 552 702 disclose polymers which contain aminal and acetal-aminal groups and which are prepared by reacting polyvinylamines or copolymers which contain vinylamine and vinyl alcohol units with aldehydes. These polymers are used as flocculants or as retention aids in papermaking.
JP-A-61/051006 discloses particulate crosslinked polyvinylamines prepared by reaction of polyvinylamines with crosslinkers, such as alkylene dihalides, epichlorohydrin or dialdehydes. The crosslinked polyvinylamines are used as ion exchangers.